If you're training for a race and have been totally avoiding high-intensity training to save your energy for running, well, you're doing it wrong. New research presented at the Experimental Biology 2016 meeting suggests that a runner's pre-race anaerobic fitness capacity (AKA the ability for your body to exercise when there's not enough oxygen) may be a key factor in determining race times.
Researchers at Simon Frasier University (SFU) in British Columbia studied 10 male mountain ultramarathoners of similar height, weight, and age, and assessed both their aerobic fitness levels and anaerobic fitness levels. Then, the researchers had the men run about 31 miles on a mountain. NBD.
Runners with a higher anaerobic capacity were predicted to have a faster finishing time. And they did. Those who scored better on the anaerobic fitness test finished faster. The researchers also observed that the runners could maintain high-intensity efforts (at greater than 80 to 85 percent of their max heart rate) for several hours.
The takeaway? Improving your anaerobic fitness could be the secret to running faster and longer. "Anaerobic capacity can be improved with high-intensity, shorter-duration training, such as in repetitive uphill sprint training," said Michael Rogers, a member of the SFU research team. However, because regular aerobic training (longer, low-intensity training) is already shown to be a good predictor of ultramarathon performance, short but difficult bursts of exercise (like in high-intensity interval training) should be done in addition to regular training, and not replace it.
Even if you're not running across mountains (though that sounds incredibly badass), you can still use HIIT cross-training to increase your anaerobic fitness and crush your next 5k, half marathon, marathon, or obstacle race. Start strong with our 30-Day HIIT Challenge, or incorporate these 13 quick and dirty moves into your current workout split. (Bonus: HIIT also does great things for your joints.)